It’s hard to believe, but Richmond’s adults-only holiday fundraiser Hamaganza celebrates two decades of charitable giving this year. That’s 20 years of hostess duties by the wheelchair-bound mound of questionable titillation, Dirt Woman. This family-unfriendly night of entertainment includes performances from small-town superstars, politicians, puppeteers, arm wrestlers and go-go dancers to raise money and hams for FeedMore, the Central Virginia hunger-relief organization. The lowbrow, lighthearted spectacle promises a big and glorious holiday debacle. Don’t miss it if you know what’s bad for you. Hamaganza is Friday, Dec. 19, at 6 p.m., at Hardywood Park Craft Brewery, and Saturday, Dec. 20, at 10 p.m., at Cary Street Café. Admission is $10 or a donation of canned ham.